IF function to avoid #DIV/0! error message

Hi

i am working out a percentage margin and a simple division sum is fine, however when the second value of the sum is missing it throws up the #DIV/0! error message, obviously because it has nothing to divide.

I am working my sum as simple as F5/E5

To avoid the message is there a way of using an IF formula to tell it to work out the sum however when cell E5 is empty or 0 then return 0 or nothing. (i.e no error message).

Your time and help is appreciated.

Thanks in advance.

Si